Holiday lights tester. Multi-purpose 12-600 VAC adjustable non-contact voltage tester with bulb and fuse tester, bulb puller. Bulb tester on the back tests both LED and incandescent light-string bulbs. Adjustable sensitivity non-contact voltage tester. 360 degree bright red light and an audible beeping indicate the presence of voltage. Requires 2 LR44 button cell batteries for operation (included). 7" height x 1.25" width x 1.2" length/depth.